Tamping or stemming plug



April 1, 1952 s. A. MORTON TAMPING OR STEMMING PLUG Filed March 17, 1948 lillllllll INVENTOR ATTORNEYS,

Patented Apr. 1, 1952 UNITED STATES PATENT OFFICE TAMPING R STEMMIN G PLUG Stanley A. Morton, Wilkes-Barre, Pa.

Application March 17, 1948, Serial No. 15,301

1 Claim.

This invention relates to tamping or stemming plugs, the primary object of the invention being to provide a plug which may be readily and easily positioned and tamped into the bore to tightly seal the bore and increase the efiectiveness of the blasting element.

Another object of the invention is to provide tamping or stemming plugs which are constructed of rock wool treated in such a way that the plug when tamped by the usual tamping stick, will expand against the wall of the bore in which the charge is being placed, the construction of the plug being such that it is unnecessary at the time of positioning the plug, to add water or other moistening fluid to cause the plug to pack.

With the foregoing and other objects in view which will appear as the description proceeds, the invention consists of certain novel details of construction and combinations of parts, hereinafter more fully described and pointed out in the claim, it being understood that changes may be made in the construction and arrangement of parts without departing from the spirit of the invention as claimed.

Referring to the drawing Figure l is an elevational view of a plug positioned in a bore for blasting, the plug having been compressed to tightly seal the bore.

Fig. 2 is an elevational view of the tamping or stemming plug.

Fig. 3 is a vertical sectional view therethrough.

Referring to the drawing in detail, a tamping or stemming plug consists of an outer casing 5 constructed preferably of transparent waterproof material filled with rock wool sprayed with a mineral oil, the rock wool being indicated by the reference character 6.

The rock wool being a fireproof materialpmay bemixed with pulverized ashes, sawdust, cork or the like, capable of packing when tamped,"and capable of expanding when compressed in a bore, to seal the bore tightly for blasting purposes.

In the construction of the plug, the casing which may also be formed of paper or fireproof material, has its ends closed around the core or material contained therein in such a way that they may be sealed against moisture. and at the same time prevent the drying out of the core or filling of the plug, to insure the sealing qualities of the plug when packed in the bore in blasting.

From the foregoing it will be seen that due to the construction shown and described I have provided a tamping or stemming plug to be used in sealing a bore in which a blasting charge has been positioned, the stemming or sealing plug being constructed of material which will readily expand and grip the wall of the bore, completely sealing the bore to'insure the effectiveness of the blast. 1

Having thus described the invention, what is claimed is:

A tamping plug comprising a tubular casing formed of fireproof flexible material, a. filling consisting of a mixture of rock wool, pulverized ashes, sawdust and cork, and a binder consisting of oil maintaining the filling in a moist and packable condition.

. STANLEY A. MORTON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,131,876 Tietig Mar. 16, 1915 2,341,944 Olsen Feb. 15, 1944 FOREIGN PATENTS Number Gountry Date 272,561 Great Britain Sept. 1, 1927 

